Apparatus for applying surgical clips

ABSTRACT

An apparatus for application of surgical clips to body tissue is disclosed having a handle assembly and an elongated body portion extending distally from the handle assembly. A jaw assembly is mounted at a distal end portion of the elongated body portion and includes first and second jaws movable between an open position and a closed position. An actuator is disclosed which is slidable within the elongated body portion in response to actuation of the handle assembly. The actuator has camming structure at a distal portion thereof for moving the first and second jaws between the open position and the closed position. A loading unit is releasably mounted to the elongated body portion and stores a plurality of surgical clips therein. The loading unit includes a clip advancer having a portion engageable with the actuator and movable therewith for advancing a distalmost surgical clip and a ratchet assembly associated with the clip advancer to index progressive movement thereof.

BACKGROUND

1. Technical Field

The present disclosure relates to apparatus for applying surgical clipsto body tissue. In particular, the disclosure relates to surgical clipappliers having a replaceable unit for storing a plurality of surgicalclips therein.

2. Description of Related Art

In the case of laparoscopic surgical procedures, access to the interiorof the abdomen is achieved through narrow tubes or cannulas insertedthrough a small entrance incision in the skin. Minimally invasiveprocedures performed elsewhere in the body are often generally referredto as endoscopic procedures. Typically, a tube or cannula device isextended into the patient's body through the entrance incision toprovide an access port which allows the insertion of various surgicalinstruments therethrough for performing surgical procedures far removedfrom the incision. During these procedures, it is often necessary toapply clips to blood vessels or various ducts to prevent the flow ofbody fluids therethrough during the procedure.

Endoscopic clip appliers are known in the art for applying a single clipduring an entry to the body cavity. Such single clip appliers aretypically fabricated from stainless steel and may be re-sterilized foruse in subsequent surgical procedures.

Endoscopic clip appliers that are able to apply multiple clips inendoscopic or laparoscopic procedures during a single entry into thebody cavity are described in commonly-assigned U.S. Pat. Nos. 5,084,057and 5,100,420 to Green et al., the disclosures of which are herebyincorporated by reference herein. Another multiple endoscopic clipapplier is disclosed in commonly-assigned copending U.S. patentapplication Ser. No. 08/134,347, filed Oct. 8, 1993, now U.S. Pat. No.5,607,436 by Pratt et al., the contents of which are also herebyincorporated by reference herein. These devices are typically, thoughnot necessarily, used during a single surgical procedure.

It is often desirable to provide a multiple endoscopic clip applier thatmay be reused during successive surgical procedures. In particular, theinternal structure of the instrument should be configured to facilitateand simplify disassembly and resterilization.

U.S. patent application Ser. No. 08/515,341 now U.S. Pat. No. 5,695, 502to Pier et al., the disclosure of which is hereby incorporated byreference herein, discloses a resterilizable surgical clip applier whichadvances and forms multiple clips during a single insertion into thebody cavity. This resterilizable clip applier is configured to receiveand cooperate with an interchangeable clip magazine so as to advance andform multiple clips during a single entry into a body cavity.

Endoscopic or laparoscopic procedures are often performed remotely fromthe incision. Consequently, application of clips may be complicated by areduced field of view or reduced tactile feedback for the user at theproximal end of the device. It is therefore desirable to improve theoperation of the instrument by providing indication to the user of theprogressive advancement of an individual clip as well as the depletionof the clip supply contained in the loading unit. It is also desirableto facilitate the complete deformation of a surgical clip prior toadvancement of a second surgical clip.

SUMMARY

The subject disclosure is directed to a unique surgical clip applyinginstrument which includes a handle assembly and an elongated bodyportion extending distally from the handle assembly. A jaw assembly ismounted at a distal end portion of the elongated body portion, andincludes first and second jaws movable between an open position and aclosed position. The body portion includes an outer sleeve having adistal nose portion configured to stabilize and guide the jaws duringmovement between the open and closed positions. The subject surgicalclip applying instrument further includes an actuator which is slidablewithin the elongated body portion in response to actuation of the handleassembly. The actuator has camming structure at a distal portion thereoffor moving the first and second jaws between the open position and theclosed position.

The subject surgical clip applying instrument further includes a loadingunit releasably mounted to the elongated body portion and storing aplurality of surgical clips therein. The loading unit has a clipadvancer having a portion engageable with the actuator and movabletherewith for advancing a distalmost surgical clip. The loading unitalso has a ratchet assembly associated with the clip advancer to indexprogressive movement thereof.

In a preferred embodiment, the actuator further includes a protrusionconfigured to engage a portion of the clip advancer. The portion of theclip advancer engageable with the actuator may be a pivoting latchmember disposed on the clip advancer. The ratchet assembly preferablyincludes a rack member disposed on the clip advancer and a pawl memberdisposed on the loading unit.

An additional feature of the subject surgical clip applying instrumentis the provision of a novel bridge portion mounted to the distal endportion of the elongated body portion adjacent the first and secondjaws. In a preferred embodiment, the bridge portion includes atransverse member in approximation with the first and second jawportions.

In a preferred embodiment of the subject surgical clip applier, theloading unit further includes a barrier member slidable within theloading unit and advanceable into a space defined between the first andsecond jaws in the open position to inhibit closure thereof. The barriermember is preferably biased towards a distal end of the loading unit.

These and other features of the subject surgical apparatus will becomemore readily apparent to those skilled in the art from the followingdetailed description of the subject disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the subject surgical apparatus are described withreference to the drawings wherein:

FIG. 1 is a perspective view of a surgical clip applier constructed inaccordance with a preferred embodiment of the subject disclosure;

FIG. 2 is a perspective view of the surgical clip applier of FIG. 1,illustrating the loading unit and the body portion separated from thehandle portion;

FIG. 3 is a perspective view with parts separated of the handle portion;

FIG. 4 is a perspective view with parts separated of the body portion,illustrating the channel member and jaw assembly;

FIG. 5 is a perspective view with parts separated of the tube housing;

FIG. 6 is an enlarged perspective view of the driver;

FIG. 7 is an enlarged perspective view of the jaw retainer disposed onthe tube housing;

FIG. 8 is a perspective view from above with parts separated of the jawassembly;

FIG. 9 is a perspective view from below of the assembled jaw assembly;

FIG. 10 is an enlarged perspective view of the distal end of the tubehousing and bridge portion;

FIG. 11 is an enlarged perspective view of the tube housing and bridgeportion of FIG. 10, illustrating the jaw assembly in position;

FIG. 12 is a perspective view with parts separated of the channel memberassembly;

FIG. 13 is an enlarged perspective view of a distal portion of thechannel member illustrating a slot for cooperating with the jawassembly;

FIG. 14 is a perspective view with parts separated of the loading unitof the subject clip applier;

FIG. 14A is an enlarged perspective view of the distal portion of theloading unit housing;

FIG. 15 is a perspective view with parts separated of the clip followerand release member;

FIG. 16 is a perspective view of the cover plate;

FIG. 16A is an enlarged perspective view of the cover plate of FIG. 16;

FIG. 17 is a perspective view from above of the clip pusher assembly;

FIG. 17A is an enlarged perspective view of the clip engaging portion ofthe clip pusher assembly;

FIG. 18 is a perspective view from below with parts separated of theclip pusher assembly;

FIG. 19 is an enlarged perspective view of the clip pusher and latchmember;

FIG. 20 is a perspective view from above with parts separated of thepawl and bracket;

FIG. 20A is a perspective view from below with parts separated of thepawl and bracket of FIG. 20;

FIG. 21 is a perspective view from below of the loading unit;

FIG. 21A is an enlarged perspective view of the loading unit,illustrating the ratchet assembly;

FIG. 21B is an enlarged perspective view from below of the distal endportion of the loading unit;

FIG. 21C is an enlarged perspective view from below of the proximal endportion of the loading unit;

FIG. 22 is a perspective view of the loading unit separated from thebody portion;

FIG. 23 is a perspective view of the loading unit mounted on the bodyportion;

FIG. 24 is a perspective view of the loading unit mounting portion;

FIG. 25 is a cross-sectional view of the handle portion with the bodyportion removed;

FIG. 26 is a cross-sectional view of the handle portion, illustratingthe pivoting handle hyperextended forward to receive the body portion;

FIG. 27 is a cross-sectional view of the handle portion of the subjectsurgical clip applier disposed in the neutral configuration;

FIG. 28 is an enlarged perspective view in partial cross-section,illustrating the interaction of the rotating knob with the body portion;

FIG. 29 is a perspective view of the subject surgical clip applier,illustrating the rotation of the body portion;

FIG. 30 is a plan view of the subject surgical clip applier;

FIG. 31 is a cross-sectional view of the body portion and loading unittaken along line 31--31 of FIG. 30, prior to advancement of thedistalmost surgical clip;

FIG. 32A is an enlarged cross-sectional view of the distal end of thebody portion and of the loading unit of FIG. 31;

FIG. 32B is an enlarged cross-sectional view of the body portion and theloading unit of FIG. 31;

FIG. 33 is a cross-sectional view taken along line 33--33 of FIG. 32B;

FIG. 34 is a cross-sectional view taken along line 34--34 of FIG. 32B;

FIG. 35 is a side view of the subject surgical clip applier,illustrating closure of the pivoting handle;

FIG. 36 is a cross-sectional view of the subject surgical clip applier,illustrating closure of the pivoting handle;

FIG. 37 is a cross-sectional view of the body portion and loading unit,illustrating the interaction of the channel member and clip pusher;

FIG. 38 is a plan view of the ratchet assembly of the loading unit;

FIG. 39 is a plan view of the ratchet assembly of FIG. 38, illustratingpivoting of the pawl member in response to translation of the clippusher;

FIG. 40 is an enlarged cross-sectional view of the ratchet assembly ofFIG. 39;

FIG. 41 is an enlarged cross-sectional view of the distal end of thebody portion and loading unit, illustrating the engagement of the clippusher and a distalmost clip;

FIG. 42 is an enlarged cross-sectional view of the distal end of thebody portion and loading unit, illustrating the advancement of thedistalmost clip into the jaw assembly;

FIG. 43 is an enlarged cross-sectional view of the body portion,illustrating the latch member pivoting out of engagement with thechannel member;

FIG. 44 is an enlarged cross-sectional view of the body portion,illustrating the clip pusher returning proximally;

FIG. 45 is a cross-sectional view of the distal end of the clip pusherreturning proximally;

FIG. 46 is an enlarged perspective view of the closure of the jawassembly to deform a clip;

FIG. 47 is a perspective view of the jaw assembly and channel member;

FIG. 48 is a plan view of the jaw assembly in a spaced apartconfiguration;

FIG. 49 is a plan view of the jaw assembly being approximated by thechannel member;

FIG. 50 is an enlarged cross-sectional view of the distal end of thebody portion and the loading unit, illustrating the advancement of theclip follower into the jaw assembly;

FIG. 51 is an enlarged perspective view of the clip follower disposed inthe jaw assemblies;

FIG. 52 is a perspective view of an alternate embodiment of the distalnose portion of the outer sleeve of the body portion;

FIG. 53 is a front view taken along lines 53--53 of FIG. 52;

FIG. 54 is a perspective view of the distal end of the body portionshown in FIG. 52 with a disposable loading unit positioned therein;

FIG. 55 is a side view of the distal end of the body portion shown inFIG. 52;

FIG. 56 is a perspective view of the distal end of the body portionshown in FIG. 52; and

FIG. 57 is a cross-sectional view taken along section line 57--57 ofFIG. 56.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The preferred embodiments of the apparatus disclosed herein will bediscussed in terms of endoscopic procedures and apparatus. However, useherein of terms such as "endoscopic" or "laparoscopic" should not beconstrued to limit the present application to an apparatus for use inconjunction with an endoscopic tube. In addition, it is believed thatthe present apparatus may find use in thoracic or arthroscopic surgerywherein access to the surgical site is achieved through a narrowcannula, or a small incision.

In the drawings and in the description which follows, the term"proximal," as is traditional, will refer to the end of the apparatuswhich is closest to the operator, while the term "distal" will refer tothe end which is furthest from the operator.

Referring now in detail to the drawings in which like reference numeralsidentify similar or identical elements, a preferred embodiment of theclip applying instrument of the subject disclosure is illustrated inFIG. 1, and is designated generally by reference numeral 10. Clipapplying instrument 10 includes handle portion 12 having pivoting ormovable handle 14 and stationary handle 16. Manipulation of thosehandles 14, 16 actuates a jaw assembly 18, through elongated bodyportion 20. A fluted rotation collar 22 is provided adjacent handleassembly 12 for remotely varying the axial orientation of the jawassembly 18 relative to handle assembly 12. Jaw assembly 18 includesfirst and second juxtaposed jaw portions 24a and 24b, which are movablebetween an approximated configuration in which jaw portions 24a and 24bare in relatively close relation to one another and a spacedconfiguration in which jaw portions 24a and 24b are separable at least asufficient distance to receive a surgical clip therebetween.

A plurality of surgical clips is stored in loading unit 26 which isreleasably mounted to elongated body portion 20. In a preferredembodiment, loading unit 26 is disposable subsequent to depletion of thesupply of clips stored therein. The remainder of instrument 10, namelyhandle portion 12 and body portion 20 may be disassembled, resterilizedand reused in combination with another loading unit containing a supplyof clips.

Movable handle 14 is shown in a neutral or "at rest" position withrespect to stationary handle 16. Pivoting movement of movable handle 14in the direction of arrow "C" towards stationary handle 16 from theneutral position defines a closing stroke. During this closing stroke, adistalmost surgical clip is advanced between the spaced apart jawportions 24a and 24b. Further closure of movable handle 14 approximatesjaw portions 24a and 24b to deform the clip. Pivoting movement ofmovable handle 14 from the neutral position away from the stationaryhandle in the direction of arrow "H" to a hyperextended positionreleases body portion 20 from handle portion 12 for separation andsterilization, as will be described below.

With reference to FIG. 2, surgical clip applying instrument 10 is shownseparated into component subassemblies, i.e. handle portion 12, bodyportion 20, and loading unit 26. As described above, hyperextension ofpivoting handle 14 permits body portion 20 to be slidably removed fromproximal end of bore 27 of handle portion 12. Loading unit 26 is removedfrom body portion 20 by actuation of release lever 28, as will bedescribed in detail below.

The Handle Portion

Turning now to FIG. 3, the components of handle portion 12 areillustrated. Handle portion 12 is designed to facilitate ease ofdisassembly and thorough resterilization prior to re-use. Handle portion12 includes housing 30, having bore 27 extending therethrough.Stationary handle 16 depends from housing 30. Pivoting handle 14 ismounted to shackles 32a and 32b of housing 30 by pivot pin 34, whichpasses through aperture 36 in pivoting handle 14 and apertures 38a and38b in shackles 32a and 32b, respectively. Housing 30 and pivotinghandle 14 are preferably formed from a biocompatible metallic alloywhich is capable of withstanding repeated resterilization procedures.

Leaf spring 40 is mounted adjacent stationary handle 16 by a pair ofretainer pins 42a and 42b. Leaf spring 40 preferably includes a pair ofkeyhole-shaped apertures 44a and 44b which facilitate locking engagementof spring 40 with retainer pins 42a, 42b and removal therefrom forresterilization. A curved portion 46 of leaf spring 40 contacts tab 48to normally bias pivoting handle 14 in the neutral position. Tab 48extends at least partially into bore 27 to maintain body portion 20therein. When pivoting handle is hyperextended, i.e. pivoted away fromstationary handle 16 such that tab 48 acts against the bias of leafspring 40, tab 48 is directed out of bore 27 to permit removal of bodyportion 20 from housing 30.

Rotation knob 22 is rotatably mounted to housing 30 at mounting sleeve50, which is formed surrounding the distal portion of bore 27 anddimensioned to receive rotation knob 22. Clip 52 is dimensioned to fitover annular notch 54 in mounting sleeve 50. Rotation knob 22 alsoincludes an annular notch (not shown), which permits rotation knob 22 tobe rotatably mounted to sleeve 50 in a snap-fitting arrangement.Rotation knob 22 further includes transverse bore 58 for the receptionof pin 60, which interlocks with body portion 20 to effect rotationalmotion, as will be described in greater detail below.

The Body Portion

With reference to FIG. 4, the elongated body portion 20 is configured tobe releasably mounted within handle portion 12 and to be disassembled tofacilitate resterilization. Body portion 20 includes outer sleeve 62defining a distal cutaway portion 64 for reception of loading unit 26.(See, FIG. 2) Outer sleeve 62 encloses channel member subassembly 66,which is configured to advance surgical clips from loading unit 26 andto actuate jaw assembly 18 to receive and deform the surgical clips. Theterms "top" or "upper" shall describe that portion of body portion 20 inproximity with loading unit 26, whereas the terms "bottom" and "lower"shall refer to the opposed portion of body portion 20.

Turning now to FIG. 5, a proximal end portion of elongated outer sleeve62 receives driver 67, which is substantially cylindrical. Asillustrated in FIG. 6, the distal portion of driver 67 includes aplurality of crenelations 68 to engage with pin 60 of rotation knob 22as will be described below. The proximal portion of driver 67 includesannular flange 70 to engage with a shoulder portion of bore 27 of handleportion 12. Driver 67 is dimensioned to provide a tight frictional fitsurrounding the proximal end portion of outer sleeve 62. Alternatively,it is contemplated that driver 67 may be welded or otherwise secured tosleeve 62.

Distal nose portion 72 of outer sleeve 62 is configured to supportloading unit 26 and jaw assembly 18. In particular, distal nose portion72 includes retainer band 74 for securing the distal end of loading unit26 in proper position. In addition, distal nose portion 72 includesnotches 76a and 76b for reception of bridge member 78. Bridge memberincludes a pair of proximally extending arms 80a and 80b configured tofit within notches 76a and 76b, respectively, and transversely extendingsupport bar 82, which is in approximation with jaw assembly 18, as willbe described in greater detail below.

FIGS. 52-57 illustrate an alternate embodiment of the distal noseportion of the outer sleeve shown generally as 272. Referring to FIGS.52 and 53, distal nose portion 272 includes retainer band 274 and bridgemember 278 which is monolithically formed with outer sleeve 262.Retainer band 274 includes a detent 275 configured to cooperate withloading unit 26 to secure the loading unit in place and ensure solidstacking of the loading unit 26, jaw assembly 18 and bridge 278 (SeeFIG. 54). Bridge member 278 includes a pair of distally extending arms280a and 280b joined together at their distal ends by a support bar 282.Alternately, bridge member 278 can be formed separately from outersleeve 262, as discussed above with respect to bridge member 78 (SeeFIG. 5).

Referring also to FIGS. 54-57, distal nose portion 272 includes a pairof diametrically opposed cutouts 290 dimensioned and configured toslidably receive jaw portions 24a and 24b. The distal end 292 of the topwall 294 defining each of cutouts 24a and 24b is angled downwardlytowards bridge member 278. During actuation of the jaw assembly 18, jawportions 24a and 24b are confined to movement in same plane definedbetween walls 294 and bridge member 278 to prevent misalignment of thejaws. Walls and bridge member 278 also provide stability to the jawassembly 18 during actuation of the jaw assembly 18.

With continued reference to FIG. 5 in conjunction with FIG. 7, thebottom surface of outer sleeve 62 includes aperture 84 for reception ofjaw retainer 86, having channel 88 for releasable mounting of jawassembly 18 to outer sleeve 62. Outer sleeve 62 further includesaperture 90 on an upper surface thereof for reception of retaining pin92, which engages a portion of channel member subassembly 66 as will bedescribed below.

With reference to FIGS. 8 and 9, jaw assembly 18 is illustrated withconstituent parts, i.e. jaw member 94 and key 96. Jaw member 94 includesfirst and second shank portions 97a and 97b joined at crown portion 98.Juxtaposed jaw portions 24a and 24b are disposed at the distal endportions of shank portions 97a and 97b. Resilience in the material, e.g.stainless steel, used to construct shank portions 97a and 97b permitsrelative approximation and spacing of jaw portions 24a and 24b.Preferably, shank portions 97a and 97b are normally biased in a spacedapart configuration. First and second shank portions 97a and 97b eachinclude a longitudinally tapering camming surface 100a and 100b forcontrol of relative approximation of jaw portions 24a and 24b inconjunction with channel member subassembly 66.

Jaw portions 24a and 24b each define an elongated channel 102a and 102bon the inner surfaces thereof for reception of a surgical clip. Crownportion 98 includes a proximally extending mounting tab 104 havingtransverse aperture 106 for the reception of key 96. As illustrated inFIG. 9, key 96 includes a cylindrical portion 108 adjacent mounting tab104 to cooperate with channel member subassembly 66, and mounting flange110 for mounting in channel 88 of jaw retainer 86.

Turning now to FIGS. 10 and 11, jaw assembly 18, as mounted in jawretainer 86 (FIG. 5), extends distally beyond nose portion 72 of outersleeve 62. Jaw portions 24a and 24b are positioned adjacent transversesupport member 82 of bridge member 78. Juxtaposition of jaw portions 24aand 24b with transverse support member 82 inhibits undesirable twistingof jaw portions 24a and 24b during surgical clip application or duringcontact with resistant tissue.

As illustrated in FIG. 12, channel member subassembly 66 includeschannel member 112, rod 114 and activating pin 116. Distal end of rod114 is secured to channel member 112 by securement pin 118, and proximalend of rod 114 is secured to activating pin 116 by securement pin 120.Collar 122 is constructed with center bore 124 to be longitudinallyslidable over rod 114. Collar 122 is limited in its distal travel bychannel member 112 and in its proximal travel by activating pin 116.Return spring 126 is slidable over rod 114 and is configured to normallybias collar 122 distally. Collar 122 is configured to engage retainingpin 92 in outer sleeve 62 to normally bias channel member subassembly 66proximally, as will be described below. A seal is provided to prohibitthe escape of gases and fluids from the operative site. Preferably,o-ring 128 is provided to fit over annular notch 130 in activating pin116 to provide the required seal. Annular shoulder portion 132 is formedat a proximal portion of activating pin to limit the distal travel ofchannel member subassembly 66 within outer tube 62.

Channel member 112 is configured to advance surgical clips from loadingunit 26 (FIG. 2) and to control the relative movement of jaw portions24a and 24b. Channel member 112 further includes distal portion 134 andintermediate portion 136. Intermediate portion 136 has a substantiallyflattened upper surface 137 and a reduced cross-section to accommodatethe components of loading unit 26 within the circumference of outer tube62. Protrusion 138 is formed on the upper surface 137 of intermediateportion 136 to transfer longitudinal displacement to the loading unit26. Preferably, protrusion 138 includes a substantially vertical distalface 139 and a substantially more shallow sloping proximal face 141.

With continued reference to FIG. 12 in conjunction with FIG. 13, distalportion 134 of channel member 112 is configured to accommodate andcontrol jaw assembly 18 (FIG. 1). Distal portion 134 includeslongitudinally elongated keyhole slot 140 terminating at its distal endin an enlarged oval shaped aperture 142. When channel member 112 is at aproximal location, aperture 142 is positioned adjacent aperture 84 inouter tube 62 (FIG. 5). Aperture 142 is sized to permit jaw retainer 86to pass therethrough for mounting to tube 62 at aperture 84 inconjunction with jaw assembly 18. Slot 140 is sized to prevent jawretainer 88 from displacing itself upward from aperture 84, but isdimensioned to permit channel member 112 to slide relative tocylindrical portion 108 of key 96. Distal portion 134 further includes apair of upright camming flanges 144a and 144b which cooperate withcamming surfaces 100a and 100b of a jaw member 94 to move jaw portions24a and 24b into approximation upon longitudinal displacement of channelmember 112, as will be described below.

The Loading Unit Subassembly

Turning now to FIG. 14, a preferred embodiment of loading unit 26 isillustrated. As described above, handle portion 12 and endoscopic bodyportion 20 are constructed to simplify disassembly and resterilization.Loading unit 26, however, is preferably constructed as a replaceableelement which is disposed of after use. The functions of storing stack146 of surgical clips 148a and 148b, of housing the clip pusher or clipadvancer 150, and of supporting a ratchet mechanism 152 to indexprogressive deployment of distalmost surgical clip 148a are performed byloading unit 26.

The internal components of loading unit 26 are supported withincartridge housing 154 which is preferably molded or machined from anengineering plastic. As illustrated in FIG. 14A, cartridge housing 154includes a pair of side walls 156a and 156b and a top surface 158. Topsurface 158 includes aperture 160 for viewing the progression ofsurgical clips. The distal portion of top surface 158 includes a pair ofsloping guide surfaces 162a and 162b for directing surgical clip 148a.Mounting slot 164 is provided for receiving a proximal end of clip guide166. Bottom plate 168 supports pawl member 170, as will be describedbelow.

Referring now to FIG. 14 in conjunction with FIG. 15, stack 146 ofsurgical clips 148a and 148b is arranged such that legs 172b of surgicalclip 148b contact crown 174a of surgical clip 148a. Surgical clip stack146 is normally biased towards the distal end of loading unit 26 by clipfollower 176 and compression spring 178 which surrounds proximalsupporting pin 180. Clip contacting portion 182 of clip follower 176 isbifurcated and configured to contact crown portion 174b of proximalmostsurgical clip 148b. Transverse bar 183 is disposed proximal to clipcontacting portion 182.

The proximal end of compression spring 178 abuts release lever 28, whichis slidable within an aperture in housing 154. Sliding of release lever28 against the bias of compression spring 178 permits the removal andmounting of loading unit 26, as will be described below.

Referring now to FIG. 16 in conjunction with FIG. 14, cover plate 184 isdisposed adjacent surgical clip stack 146 and clip follower 176, andmaintains surgical clip stack in alignment. The distal end portion ofcover plate 184 includes a pair of guide flanges 186a and 186b to directsurgical clip 148a into the jaw portions. Transverse protrusions 188aand 188b in guide flanges 186a and 186b cooperate with clip guide 166 toact as a stop for retaining surgical clip 148a in position prior toadvancement thereof by clip pusher 150.

As illustrated in FIGS. 16 and 16A, cover plate 184 includes flange 190to limit the proximal longitudinal travel of the clip pusher. Theproximal end portion of cover plate 184 includes downwardly extendingleaf spring 192, which facilitates separation and removal of the loadingunit from the body portion.

Referring to FIGS. 17-19, clip pusher 150 is configured to advance asurgical clip into the jaw portions. As illustrated in FIG. 17, thedistal portion of clip pusher 150 includes a clip advancing arm 194formed of a resilient material. Clip advancing arm 194 advances surgicalclips through a non-linear path adjacent guide surfaces 162a and 162b ofcartridge housing 154 (FIG. 14A) and into elongated channels 102a and102b of jaw portions 24a and 24b (FIG. 8). As best seen in FIG. 17A,clip advancing arm 194 terminates in a clip engaging portion 196 havinga pair of sloping trailing edges 198a and 198b and a pair ofsubstantially vertical leading edges 200a and 200b. Clip engagingportion 196 is configured such that leading edges 200a and 200b contactcrown portion 174a of surgical clip 148a.

Turning now to FIG. 18, clip pusher 150 includes a spring mountingflange 202, at which return spring 204 (not shown) is connected tonormally bias clip pusher 150 proximally, as will be described below.Guide channel 206 is defined in clip pusher 150 and cooperates withflange 190 in cover plate 184 to limit the proximal range of movement ofclip pusher 150. A series of ratchet teeth 208 are defined adjacent tochannel 206 to increment advancement of clip pusher 150, as will bedescribed below.

Latch member 210 is pivotably mounted at the proximal portion of clippusher 150 by means of a pair of shackles 212a and 212b in clip pusher150 and pivot pin 214 passing therethrough and through shackles 216a and216b in latch member 210. Torsion spring 218 normally biases latchmember 210 in a downward direction as indicated by arrow "L" in FIG. 19.Latch member 210 is configured to be contacted by protrusion 138 ofchannel member 112 to advance surgical clips as will be described below.

With reference to FIGS. 20-20A in conjunction with FIG. 21, ratchetassembly 152 includes pawl 170, which is mounted to bottom plate 168 atpawl mount 153 by pawl mounting bracket 222. Pawl 170 includes asubstantially cylindrical portion 224 having notch 226 extendingpartially therethrough, and a flange portion 228 having tooth 230 forengaging rack 208 of clip pusher 150. Pawl mounting bracket 222 has asubstantially "U" shaped configuration, including a pair of arms 232aand 232b joined at crown portion 234. Arm 232a defines a pair ofapertures 236a and 236b for mounting on nodes 238a and 238b of bottomplate 168. Arm 232b defines an elongated slot 240 including arcuatenotch 242 for mounting pawl 170 thereto adjacent notch 226.

In the assembled configuration of loading unit 26 as illustrated inFIGS. 21 and 21A, pawl 170 extends into position adjacent rack 208 ofclip pusher 150. Return spring 204 is mounted to bottom plate 168 tonormally bias clip pusher 150 proximally.

With reference to FIG. 21 in conjunction with FIG. 21B, guide flanges186a and 186b cooperate with clip guide 166 to act as a stop forretaining surgical clip 148a in position prior to advancement by clippusher 150. Clip engaging portion 196 passes between guide flanges 186aand 186b to advance surgical clip 148a at crown 172a beyond clip guide166 to jaw portions 24a and 24b (not shown).

With reference to FIG. 21 in conjunction with FIG. 21C, leaf spring 192extends downwardly to provide or facilitate separation and removal ofloading unit 26 from body portion 20 by providing a force againstchannel member 112.

Turning now to FIG. 22, loading unit 26 is mounted to body portion 20 byinserting the distal portion of cartridge housing 154 beneath retainerband 74. Release member 28 is advanced distally as indicated by arrow"M". As illustrated in FIGS. 23 and 24, release member 28 is permittedto move to its normally biased position in the direction of arrow "R" tosecure loading unit 26 to body portion 20.

Operation of the Instrument

FIG. 25 illustrates pivoting handle 14 in the neutral position. Tab 48partially extends into bore 27 prior to insertion of body portion 20. Asdepicted in FIG. 26, hyperextension of pivoting handle 14 in thedirection of arrow "H" against the bias of leaf spring 40 moves tab 48out of the plane of bore 27. Body portion 20 is inserted into bore 27from the proximal end of housing 30 in a distal direction as indicatedby arrow "D". FIG. 27 illustrates that the distal end of activating pin116 has been advanced distal to tab 48 until flange 70 of driver 67contacts shoulder portion 220 of bore 27. Pivoting handle 14 isthereupon released and curved portion 46 of leaf spring 40 resumes itsunbiased shape and returns pivoting handle 14 to the neutral position.Tab 48 is thereby positioned proximal to activating pin 116.

The rotation control feature of instrument 10 is illustrated in FIGS.28-29. As depicted in FIG. 28, body portion 20 is inserted into bore 27such that pin 60 of rotation knob 22 contacts one crenelation 68 ofdriver 67. The interlocking of crenelation 68 with pin 60 permits remoteaxial rotation of the tool assembly, as shown in FIG. 29.

FIGS. 30-34 depict the body portion 20 and loading unit 26 of instrument10 prior to advancement of a surgical clip. FIG. 31 illustrates stack146 of surgical clips 148a, 148b stored in loading unit 26. Channelmember 112 is disposed in a proximal position. Referring to FIG. 32A,the distal portion of loading unit 26 is shown in position adjacent bodyportion 20. Distalmost surgical clip 148a is biased distally bycompression spring 178 and held in position at crown portion 174athereof by clip guide 166 and transverse ridges 188a (not shown) and188b of cover plate 184. Clip engaging portion 196 of clip pusher 150 isdisposed in an initial position spaced from crown portion 174a.

As illustrated in FIG. 32B, latch member 210 is biased downward intocontact with channel member 112. Channel member 112 is initiallydisposed in a proximal position such that protrusion 138 is spaced fromlatch member 210. With reference to FIG. 32B in conjunction with FIG.33, cover plate 184 maintains surgical clips 148b in proper alignmentfor advancement into jaw portions 24a and 24b (not shown). Asillustrated in FIG. 32B in conjunction with FIG. 34, cover plateretainer clip 244 is substantially U-shaped having a pair of arms 246aand 246b including flanges 248a and 248b disposed in notches 250a and250b in cartridge housing 154. Retainer clip 244 maintains a distalportion of cover plate 184 in position.

Turning to FIGS. 35 and 36, closure of pivoting handle 14 in thedirection of arrow "C" actuates the tool assembly. As illustrated inFIG. 36, closure of pivoting handle 14 advances tab 48 in an arcuatepath in a generally distal direction as indicated by arrow "D". Tab 48contacts activating pin 116, thereby advancing activating pin 116, rod114, and channel member 112 distally against the bias of return spring126.

With reference to FIG. 37, channel member 112 is advanced distally asdescribed above. Upon advancing a predetermined distance, distal surface139 of protrusion 138 engages downwardly biased latch member 210. Atthat point, clip pusher 150 is conveyed distally by channel member 112against the bias of return spring 204.

Turning now to FIGS. 38-40, operation of ratchet mechanism 152 will nowbe described with respect to the advancement of clip pusher 150. Withreference to FIG. 38, engaging tooth 230 of pawl member 170 is normallybiased by support arm 232b into engagement with rack 208 of clip pusher150. Consequently, the position of clip pusher 150 to bottom plate 168is maintained. As a result, if pivoting handle 14 is released, returnspring 126 will return channel member 112 proximally, but clip pusher150 and distalmost surgical clip 148a are maintained in position.Subsequent closure of handle 14 will advance channel member 112 distallyand thereby re-engage protrusion 138 with latch member 210. In this way,surgical clip 148a is advanced into jaw portions 24a and 24b beforesubsequent surgical clip 148b is advanced, thereby preventing jamming ofinstrument 10. As illustrated in FIGS. 39-40, advancement of clip pusher150 pivots pawl member 170 out of engagement with rack 208. Inparticular, rotation of pawl member 170 causes arm 232b to momentarilydeform from its normal position.

FIG. 41 illustrates how closure of pivoting handle 14 further advancesclip pusher 150. In particular, clip engaging portion 196 of clip pusher150 advances crown portion 174a of distalmost surgical clip 148a beyondclip guide 166 and transverse protrusions 188a (not shown) and 188b ofguide flanges 186a (not shown) and 186b. Further closure of pivotinghandle 14 advances clip pusher 150 toward the jaw portions as shown inFIG. 42. Distalmost surgical clip 148a is driven by clip engagingportion 196 into elongated notches 102a and 102b of jaw portions 24a and24b for subsequent deformation thereby.

As illustrated in FIG. 43, following the advancement of surgical clip148a, rack member 208 disposed on clip pusher 150 is advanced beyondpawl member 170 and latch member 210 is configured such that shackles216a and 216b contact pawl mount 153 on bottom plate 168. At that time,latch member 210 pivots upward against the bias of torsion spring 218,and out of engagement with protrusion 138 of channel member. As depictedin FIG. 44, clip pusher 150 returns proximally subject to the bias ofreturn spring 204. FIG. 45 illustrates that clip engaging portion 196 ofclip pusher 150 moves proximally from between jaw portions 24a and 24b.Sloping trailing edges 198a and 198b along with the resilientcharacteristics of clip advancement arm 194, enable clip engagingportion 196 to ride over crown portion 174b of the next surgical clip148b, which has been advanced distally by clip follower 176. Withcontinued reference to FIGS. 44 and 45, channel member 112 is permittedto continue advancing distally.

Closure of jaw portions 24a and 24b, as depicted in FIG. 46, deformssurgical clip 148a held therebetween. As illustrated in FIGS. 47-49,channel member 112 is advanced distally with respect to jaw assembly 18,which is maintained stationary. It is noted that the jaws remainstationary until the surgical clip is moved into final position betweenthe jaws. Camming flanges 144a and 144b progressively approximate jawcamming surfaces 100a and 100b. Referring to FIG. 48, camming flanges144a and 144b are disposed adjacent shank portions 97a and 97b and jawportions 24a and 24b are in the normally spaced apart configuration forreception of a surgical clip. With further advancement of channel member112, as in FIG. 49, camming flanges 144a and 144b engage jaw cammingsurfaces 100a and 100b. Due to the configuration of camming surfaces100a and 100b, which widen towards the distal portion thereof, furtherdisplacement of channel member 112 causes jaw portions 24a and 24b toapproximate, thereby deforming a surgical clip.

The above described operation of advancing a distalmost clip to the jawportions, retracting the clip pusher proximally, and deforming the clipis repeated sequentially until the last surgical clip has been advancedfrom loading unit 26. After the proximalmost surgical clip has beenapplied, clip follower is biased distally by compression spring 178 andretained in position by clip guide 166, which acts on transverse bar183. As described above, closure of pivoting handle 14 operativelyadvances clip pusher 150. Clip engaging portion 196 of clip pusher 150engages transverse bar 183 of clip follower 176 and advances clipfollower 176 beyond clip guide 166 and into elongated slots 102a and102b of jaw portions 24a and 24b as illustrated in FIG. 50.

With reference to FIG. 51, clip follower 176 is advanced between jawportions 24a and 24b. Clip follower 176 is constructed of an engineeringplastic that is sufficiently rigid to prevent closure of jaw portions24a and 24b when clip follower 176 is disposed therebetween.Consequently, the surgeon is provided with tactile indication of thedepletion of surgical clips from loading unit 26 because channel member112 and pivoting handle 14 are prevented from further motion. Clipfollower 176 is also preferably fabricated in an bright color to providevisual indication that the loading unit 26 has been emptied of surgicalclips. In addition, when the bright coloration of clip follower 176becomes visible in viewing aperture 160, loading unit 26 only contains afew remaining surgical clips and the surgeon receives early indicationof this fact.

It will be understood that various modifications may be made to theembodiments shown herein. Therefore, the above description should not beconstrued as limiting, but merely as exemplifications are preferredembodiments. Those skilled in the art will envision other modificationswithin the scope and spirit of the claims appended hereto.

What is claimed is:
 1. An apparatus for application of surgical clips tobody tissue, which comprises:a) a handle assembly; b) an elongated bodyportion extending distally from the handle assembly, the elongated bodyincluding an outer sleeve having a distal nose portion having a pair ofcutouts; c) a jaw assembly mounted at a distal end portion of theelongated body portion, the jaw assembly including first and second jawsmovable between an open position and a closed position; d) an actuatorslidable within the elongated body portion in response to actuation ofthe handle assembly, the actuator having camming structure at a distalportion thereof for moving the first and second jaws between the openposition and the closed position; and wherein each of the jaws arepositioned at least partially within one of the cutouts during movementof the jaws between the open and closed positions to stabilize and guidethe jaw assembly.
 2. An apparatus according to claim 1, wherein theelongated body portion is adapted to releasably receive a loading unit.3. An apparatus according to claim 2, wherein the distal nose portionalso includes a retainer band having a detent formed therein, the detentbeing configured to engage a disposable loading unit received within theelongated body portion.
 4. An apparatus according to claim 1, whereinthe distal nose portion further includes a bridge member, the bridgemember being positioned on a first side of the first and second jaws. 5.An apparatus according to claim 4, wherein each of the cutouts includesa top wall, the top wall being positioned on a second side of the firstand second jaws, the first and second jaws being confined to movement ina plane defined between the top wall of each of the cutouts and thebridge member.
 6. An apparatus according to claim 5, wherein the topwall is angled downwardly towards the bridge member.
 7. An apparatusaccording to claim 1, wherein the elongated body portion islongitudinally fixed with respect to the handle assembly.
 8. Anapparatus according to claim 1, wherein the jaw assembly is positionedat least partially within the elongated body portion and each of thejaws has a camming surface, the actuator being slidable into engagementwith the camming surface of the jaws to move the jaws to the closedposition.